Bubble generator for a bathtub



FIG. 1 is a front elevational view of a bubble generator for a bathtub showing my new design;

FIG. 2 is a rear elevational view thereof;

FIG. 3 is a top plan view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a right side elevational view thereof, the left side being a mirror image; and

FIG. 6 is a cross-sectional view thereof, as taken on line 6--6 of FIG. 1. 

The ornamental design for a bubble generator for a bathtub, as shown and described. 